import pandas as pd

# 新建一列为freq_all/flow
# 导入数据
data = pd.read_csv(r'D:\ceshi_python\nihe_fjpg\test\data.csv', sep='\t')
data['freq_all_flow'] = data['freq_all'] / data['flow']

#data = data[data['heat_load']<400]
data.to_csv('data.csv', sep='\t', index=False)